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Sending of the message failed. Peer reports incompatible or unsupported protocol version.

  • 2 replies
  • 2 have this problem
  • 22 views
  • Last reply by sfhowes

NCzeroK
NCzeroK
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Thunderbird had been working on all my computers till this morning. Now, when I try to send email, I get the following error message: Sending of the message failed. Peer reports incompatible or unsupported protocol version.

I tried downloading a new Thunderbird, still get the same error message. Don't have a clue as to where to go or what to do.

Thunderbird had been working on all my computers till this morning. Now, when I try to send email, I get the following error message: Sending of the message failed. Peer reports incompatible or unsupported protocol version. I tried downloading a new Thunderbird, still get the same error message. Don't have a clue as to where to go or what to do.

All Replies (2)

firefox1117
firefox1117
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Hi, are you using Eset firewall? There seems to be an update was released which blocks some parts of Thunderbird. Try to disable it by right clicking on the icon in the system tray > Advanced settings > Web and email, and disable the options there.

sfhowes
sfhowes
  • Top 10 Contributor
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https://support.mozilla.org/en-US/questions/1295861